• Bulletin of the Korean Chemical Society
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• v.31 no.3
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• pp.620-623
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• 2010

A brush type chiral stationary phase (CSP 2) derived from ${\alpha}$-amino ${\beta}$-lactam was prepared for the separation of the enantiomers of ${\beta}$-blockers. Compared to the CSP derived from ${\alpha}$-amino phosphonate (CSP 1), in general, the conformationally rigid CSP 2 showed greater scope and much enhanced enantioselectivity for the resolution of ${\beta}$-blockers. The effect of various salt additives on enantioseparation of ${\beta}$-blockers in the mobile phase was investigated. The unusual effect of temperature on the chromatographic behaviors was observed on CSP 2. It also afforded appreciable increases in enantioselectivity without significantly affecting resolution, as the column temperature was reduced.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.506-510
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• 2003

SMB(simulated moving bed) chromatography system has been developed to realize continuous separation and save solvent consumption for binary mixture in especial. The parameters of SMB chromatography system can be calculated from mass balance equations of true moving bed chromatography, and they are used in design of 6-column SMB chromatography. We can separate S-ketoprofen enantiomer as a raffinate product in 85% of purity and 0.3mg/ml using assembled SMB chromatography system.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.435-438
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• 2003

Epoxide hydrolase(EH) catalyze the enantioselective hydrolysis of racemic epoxides to corresponding diols. A recombinant Pichia pastoris with EH from Rhodotorula glutinis has been constructed by reverse transcriptase-polymerase chain reaction(RT-PCR). The recombinant biocatalyst enantioselectively hydrolyze (R)-styrene oxide faster than (S)-enantiomer. The catalytic activity of recombinant biocatalyst was 7-fold higher than that of wild-type strain. The recombinant EH biocatalyst can be used for kinetic resolution for the production of enantiopure styrene oxide.

• Mass Spectrometry Letters
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• v.2 no.4
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• pp.88-91
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• 2011

The pharmacokinetic properties of S-amlodipine were studied using racemic amlodipine and single S-enantiomer (SK310) administration to rats. Plasma levels of the drug were determined using chiral liquid chromatography coupled with tandem mass spectrometry following solid phase extraction. The stereospecific analysis of amlodipine was performed on an ${\alpha}$-acid glycoprotein (AGP) column using a mobile phase comprising 10 mM ammonium acetate (pH 4.0) and propanol at a flow rate of 0.2 mL/min. This method was used to perform a comparative study of the pharmacokinetics of amlodipine and SK310. The results revealed that the pharmacokinetic profile of S-amlodipine after the administration of SK310 was comparable to that following the administration of the racemic mixture.

• Journal of Pharmaceutical Investigation
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• v.18 no.2
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• pp.69-81
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• 1988

We studied on the synthesis of chloromethylated polystyrene as a precursor of optically active polymers for direct resolution of optical isomers. Changing the degree of crosslinking and the kind of crosslinking agents, several polystyrene resin matrices were synthesized. The matrices were chloromethylated with methylal and chlorosulfonic acid as chloromethylating agents. The effects of solvents of various dielectric constants on the chloromethylation were quantitavely examined. We also synthesized chloromethylated polystyrene of macroreticular type that retained large surface area and good physical stability. The differences between the macroreticular type and macroporous type were investigated.

• Journal of Pharmaceutical Investigation
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• v.18 no.2
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• pp.83-88
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• 1988

We examined effects of crosslinking agents, i.e., ethyleneglycol dimethacrylate (EGD) and butanediol dimethacrylate (BDD) containing ester groups on chloromethylation of crosslinked polystyrene resin matrices. It was proved that the ester group in methylmethacrylate (MMA) accelerates the chloromethylation of the divinylbenzene (DVB)-crosslinked styrene-MMA copolymer. As the MMA content increased in the styrene-MMA copolymers, the chloromethylation was enhanced. Complete chloromethylation was obtained at about 25% MMA content.

• Natural Product Sciences
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• v.6 no.1
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• pp.20-24
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• 2000

The enantiomers of higenamine were directly separated by high performance liquid chromatography using a chiral stationary phase and detected by UV. The R- and S-isomers of higenamine were eluted at the retention time of 22 min and 27 min, respectively. Higenamine was determined to be present as R-(+)-enantiomer not only in the embryo of Nelumbo nucifera, from which the separation of R-(+)-higenamine was reported, but also in various Aconite roots, from which higenamine was separated as optically inert racemic mixtures.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.400.3-401
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• 2002

Levosulpiride is the levo-enantiomer from of racemic sulpride. abenzamide derivative selectively inhibition doparninergic D2 receptos at the trigger zone both in the central nervous system and in the gastrointestinal tract. We report a rapid and sensitive HPLC method using reverse phase C 18 column with fluorescence detection for separation and quantitation of levosulpiride in plasma. Tiapride was used as an internal standard. After adding an internal standard. levosulpiride in 800 ${\mu}l$ of plasma was extracted under basic conditions with ethyl acetate and methylene chloride. (omitted)

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.404.3-405
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• 2002

Cupressaceae plants are used in traditional folk medicine. whose extracts have been found to possess some bioactivities. (－)-Yatein is a lignan of the dibenzyl-butyrolactone type. that has been isolated from some Cupressaceae plants. It was reported that (－)-yatein. isolated from plants. showed different activities from the synthetic yatein ［3］. Hence. the enantiosetective determination of yatein from synthetic materials and natural products would be necessary. (omitted)

• YAKHAK HOEJI
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• v.33 no.1
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• pp.64-71
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• 1989

Since time-dependent inactivation of MAO was found to be complete in a few minutes when high concentration ratios of tranylcypromine to MAO were used, a method to obtain kinetic parameters was sought suitable to the conditions in which concentrations of tranylcypromine analogs did not exceed that of MAO. For the purpose, kinetic equations were derived and the method applied to the kinetic studies of tranylcypromine enantiomers. It was found that (E)-(+)-2-phenylcyclopropylamine inhibited MAO by the mechanism following bimolecular reaction scheme with $\tilde{K}_i$ of $2.0\;{\times}\;10^6M^{-1}min^{-1}$. Whereas, MAO-inhibitory pattern of the (-)-enantiomer was to be interpreted by suicide inhibition scheme and measured $k_{in}\;and\;\tilde{K}'$ were $0.457\;min^{-1}\;and\;$5.4{\mu}M$, respectively.